A flash flood tore through Nepal's Gorkha district early on Sunday, sweeping away homes and bridges. Experts said a landslide and a temporary river blockage likely triggered the disaster. Pema Gyamtsho said, "Understanding what triggered this flood will be critical for reducing future risks and strengthening resilience." Rescue efforts continue.

A flash flood tore through Nepal's Gorkha district early on Sunday, sweeping away homes, bridges, and damaging hydropower infrastructure.

A landslide and the possible breach of a temporary river blockage may have triggered the flash flood in Nepal's Budhi Gandaki river system, according to a Kathmandu-based intergovernmental organisation.

Landslide, temporary river breach

The flash flood that swept through the Budhi Gandaki river system may have been triggered by the failure of a temporary river blockage created by a landslide near Chumchet in Gorkha district, the International Centre for Integrated Mountain Development (ICIMOD) reported, citing preliminary accounts from Nepali authorities.

The ICIMOD, in a statement, said that flooding is estimated to have begun around 4 am (local time), carrying mud, sediment and debris downstream through the Budhi Gandaki corridor.

Pema Gyamtsho, ICIMOD Director General, said the devastating flood that caused destruction Sunday underscored the risks posed by cascading mountain hazards, in which one event can trigger another.

"While response efforts must remain the immediate priority, understanding what triggered this flood will be critical for reducing future risks and strengthening resilience," Gyamtsho said.

Furthermore, ICIMOD also noted that the flood highlighted the vulnerability of transport networks, energy infrastructure, essential services, and settlements along mountain river corridors.

It added that understanding how slope instability, river dynamics and downstream exposure interact would be crucial for risk reduction, infrastructure planning and recovery efforts in the Himalayas.

The Kathmandu-based ICIMOD is an intergovernmental organisation working on sustainable development and environmental challenges in the Hindu Kush Himalaya region, according to news agency PTI.

What happened in Nepal flash flood?

Following the flood, at least 10 people remain missing, while nearly 50 people have been rescued, the report added, citing Nepali authorities.

Search and rescue operations, evacuations and relocation efforts are underway.

Furthermore, the floodwaters also reportedly swept away a construction camp and equipment at the 341-MW Budhi Gandaki hydropower project in Salleri. The full extent of the damage remains unclear.

Nepal's August flash floods

The latest incident comes just weeks after the catastrophic flash floods that hit Nepal's mountainous border regions on August 26.

The devastating tragedy claimed more than 1,400 lives and left thousands missing.

The flash floods devastated towns and villages in northern and central Nepal, leaving a trail of destruction.